Question: Khan.scratchpad.disable(); For every level William completes in his favorite game, he earns $840$ points. William already has $380$ points in the game and wants to end up with at least $2660$ points before he goes to bed. What is the minimum number of complete levels that William needs to complete to reach his goal?
Answer: To solve this, let's set up an expression to show how many points William will have after each level. Number of points $=$ $ $ Levels completed $\times$ Points per level $+$ Starting points Since William wants to have at least $2660$ points before going to bed, we can set up an inequality. Number of points $\geq 2660$ Levels completed $\times$ Points per level $+$ Starting points $\geq 2660$ We are solving for the number of levels to be completed, so let the number of levels be represented by the variable $x$ We can now plug in: $x \cdot 840 + 380 \geq 2660$ $ x \cdot 840 \geq 2660 - 380 $ $ x \cdot 840 \geq 2280 $ $x \geq \dfrac{2280}{840} \approx 2.71$ Since William won't get points unless he completes the entire level, we round $2.71$ up to $3$ William must complete at least 3 levels.